Between the date when a new vehicle leaves an assembly line and the date that that vehicle is taken over by its purchaser, many weeks often elapse, required for the transportation of said vehicle between its place of production and the final dealer.
During this period, the electrical consumption of the vehicle has to be as low as possible in order to avoid a discharging of the battery and, for this reason, each vehicle is initially configured in a mode, called transport mode, in which all the usual functions of the “car interior” computer are deactivated, apart from a function, performed by the microprocessor of this computer, of monitoring the state of an electrical switch connected in such a way that a change of state of said electrical switch constitutes an event triggering a switchover of said computer between its transport mode and the customer mode in which all its functions are reestablished. As an example, the electrical switches used can be the switches inserted into the handles of the vehicles in order to control the unlocking of the doors, the switch actuated by the vehicle ignition key, etc.
Such a transport mode therefore requires only the microprocessor to be powered in order for the latter to periodically monitor the state of each electrical switch concerned, and, in practice, the electrical consumption inherent in this transport mode is in the order of 400 microamperes-hour to a few milliamperes-hour.
Such an electrical consumption proves sufficiently low to serve as a guarantee, in most cases, against a total discharge of the batteries of the vehicles.
However, it has been found that, given the maximum transportation times added to the storage periods, a total guarantee could be obtained only if the electrical consumption is in the vicinity of 100 microamperes-hour.